In what police called an act of domestic terrorism, a gunman opened fire in a Sikh temple in Wisconsin Sunday, killing at least six and injuring three others before being shot and killed in the parking lot. The gunman shot one officer several times before he was killed by another officer.

Sikhism, a major religion with about 25 million adherents worldwide, remains little known and widely misunderstood in the United States, where turban-wearing Sikh men are often mistaken for Muslims. In fact, said Harpreet Singh, a doctoral student in religion at Harvard University, nearly all people who wear turbans in the United States are Sikhs.
“We don’t want to say, ‘We are not Muslims,’ because that has the implication of, ‘Don’t attack us, attack them,’ ” he said.

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